Their son was painfully shy.

他们的儿子非常害羞。

《牛津词典》

Their son is a real personality.

他们的儿子真是有个性。

《牛津词典》

They named their son John.

他们给儿子起了个名字叫约翰。

《牛津词典》

A wife might urge her husband to "go easy on" their son, because the boy did not mean to wreck the car.

VOA: special.2009.06.07

And after he graduated, he entered the service of an aristocratic family, the Cavandish family, where he became a private tutor to their son.

他毕业后，开始为一个贵族世家工作，也就是卡文迪许家族，在那里他成为了他们儿子的私人教师。

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And they tell you about their son and how handsome he is.

他们跟你谈论自己的儿子，告诉你他有多英俊。

It sounds like 课堂 - SpeakingMax英语口语达人

Parents, for example, often see that their son or daughter is developing depression or a psychosis.

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He was able to coach their son's soccer team, and he never missed a ballet recital.

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Their bodies were discovered by their son, Jason, who is an officer with West Midlands Police.

BBC: Birmingham deaths: Man arrested on suspicion of murder